I have been subject to respiratory infections my entire life. Thank God medication like Claritin are wonderful prophylactics. However, occasionally I am in your situation. The only thing that helps my ears are to take two styrofoam cups, 2 small cloths, and get the FA to pour a small amount of hot water on the cloths. Then hold the cups over your ears on landing. OK, you look like a doofus - but it's a heck of a lot better than excruciating pain. The moist hot air helps the ear channels expand - ahhhh, good.
Occasionally the FA will refuse to provide the hot water due to our litigious society. God forbid, you could burn your ears. Then ask for hot water for a cup of tea.
